func (m *OWLQNMinimizer) fixDirSign(dir *core.Vector, steepestDescDir *core.Vector) {
if m.l1reg == 0 {
return
}
for key, val := range dir.Data {
if val*steepestDescDir.GetValue(key) <= 0 {
dir.SetValue(key, 0)
}
}
}
// Description: assume all the features in x also appears in grad
func (m *OWLQNMinimizer) updateGrad(x *core.Vector, grad *core.Vector) {
if m.l1reg == 0 {
return
}
for key, val := range grad.Data {
xval := x.GetValue(key)
if xval < 0 {
grad.SetValue(key, val-m.l1reg)
} else if xval > 0 {
grad.SetValue(key, val+m.l1reg)
} else {
if val < -m.l1reg {
grad.SetValue(key, val+m.l1reg)
} else if val > m.l1reg {
grad.SetValue(key, val-m.l1reg)
}
}
}
return
}
// Description: assume all the features in x also appears in grad
// all the features in dir must be in grad
func (m *OWLQNMinimizer) updateGradForNewPos(x *core.Vector, grad *core.Vector, dir *core.Vector) {
if m.l1reg == 0 {
return
}
for key, val := range grad.Data {
xval := x.GetValue(key)
if xval < 0 {
grad.SetValue(key, val-m.l1reg)
} else if xval > 0 {
grad.SetValue(key, val+m.l1reg)
} else {
dirval := dir.GetValue(key)
if dirval < 0 {
grad.SetValue(key, val-m.l1reg)
} else if dirval > 0 {
grad.SetValue(key, val+m.l1reg)
}
}
}
return
}
